The present invention relates to production of capacitor grade tantalum powder of high specific capacitance, low specific leakage and high breakdown voltage.
Generally, finer powders of tantalum can be achieved when producing tantalum from fluotantalate salt sources by sodium reduction, with higher and higher dilutions of the source with NaCl and like diluents. However, the higher dilutions lead to more alkalli pick-up by the tantalum and consequently higher leakages and lower breakdown voltages.
It is a basic object of the invention to nevertheless utilize high dilution reductions in an effective way avoiding such pitfalls.